Abstract: PURPOSE: To compare the results of two deformation registration softwares of CT deformation registration in image registration and select a reasonable deformation registration software. METHODS: Fifteen reposition patients with head and neck cancer were collected, the normal tissues of the two groups of CT images were contoured by the same senior doctors, then the deformation and registration proceeded in MIM software and AccuContour software respectively. The normal tissues of the first group were deformed into the second group, and the tissues directly delineated by the second group were calculated to obtain the similarity coefficient (Dice coefficient) and spatial evaluation index (Hausdorff distance). SPSS 23. 0 software package was used for data analysis. RESULTS: Both of the two softwares had good deformation and registration function. Different imaging results of normal tissues had a certain impact on the registration results. The registration results of tissues with good imaging such as eyeball and mandible were better, while the registration results of tissues with small volume such as crystal, optic nerve and optic chiasm were relatively poor. Among the comparison results of the two groups of softwares, MIM software had more advantages. In the evaluation of Dice coefficient, the ratio of MIM software with better data was 67%, 55% of which was statistically significant(P< 0. 05). Hausdorff distance showed that the ratio of MIM software data was better was 74%, of which 48% indicators had statistical significance(P< 0. 05). CONCLUSIONS: In the aspect of deformation registration, both kinds of deformation registration softwares had good deformation registration ability. In comparison, MIM software has more advantages, and it is better to choose MIM software when the requirement of deformation registration accuracy is high.

Key words: Deformation registration, MIM software, AccuContour software, Monaco treatment planning system, Head and neck tumour